Grounding problem, please help

I have a 220 circuit running from my barn to my well house. The meter is at the barn and the feeders connect in the box containing the meter. There are three wires connecting the well house, all three black with one having a white stripe. I assume the one with the white stripe is the neutral. The wires run underground until they reach the well house and then one is yellow inside. After testing with a meter the yellow is the neutral the two black each have 120v.

My well pump is 220 and works fine with or without the yellow wire connected to the breaker box.

If I connect a single 30 amp breaker to the braker box that connects to one phase of the circuit (120v) and put a load on the circuit, it drops all voltage.

I assume there is a problem with the main yellow (and then black with white stripe) wire that goes back to the meter.

Any ideas or suggestions? Also, how can the 220 work without the neutral to complete the circuit?

Thanks.

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You need to do some more research. Are you telling us that the feeder to the pump comes straight off the meter lugs? If so that makes them unfused service conductors. Does the pump house have any type of electrical panel?

The neutral balances the potential voltage between the two legs. If you measure voltage across the two hots, you should see about 240V. Measuring between either hot and the neutral should result in 120V.

You need to describe your setup in a little more detail. You mentioned a breaker box... does your service from the meter connect to a breaker box, and the pump is connected to breaker in that box?

Also, what exactly are you trying to accomplish with a 30A 120V circuit? That's a bit hefty for a 120V circuit (although not entirely out of the question).

Grounding problem, please help

I put a 30 amp breaker in because I tripped the 20 amp with the heat lamp I put in the well house last winter to thaw the pipes. I will put a permanent heat lamp in there this winter with a thermostat to automatically turn on at about 38 degrees.

The well pump really doesn't come into play with the problem. I removed the 50 amp breaker for the pump completely from the breaker box and still had the same problem. The only thing I had on the breaker box was the 120v breaker and the voltage still went to zero with a load.

I see ~250v across the two legs combined and 120v each so I know both are working fine.

Yes, the service from the meter connects to the new breaker box I put in about a year and a half ago. Everything worked fine until I plugged in the heat lamp and tripped the breaker (or whatever damage it did). I have also replaced the 120v breaker with a new breaker with the same result.

Logically, the only thing left that hasn't been replaced is the Neutral wire that connects the breaker box to the service from the meter.

corsair

The service comes from the meter and feeds into a new breaker box in the well house. One black wire feeds the top bus and the other black wire feeds the bottom bus. The yellow wire is connected to the grouding strip on top.

The pump has it's own electrical box that feeds from the breaker and then goes to the pump.

However, even if I take the entire pump loop out of the process, I have the same problem with the outlet losing voltage. I removed the pump breaker from the breaker box.

Also, I consulted a local home improvement store and spoke with the resident "expert". He suggested a ground wire connected to a grounding rod driven in the ground. I ran a number 8 copper wire outside the well house and drove a steel rod 5 feet in the ground and connected the two. I connected the copper wire to the grounding strip on the top of the breaker box. I got the same results.

Also, I consulted a local home improvement store and spoke with the resident "expert". He suggested a ground wire connected to a grounding rod driven in the ground. I ran a number 8 copper wire outside the well house and drove a steel rod 5 feet in the ground and connected the two. I connected the copper wire to the grounding strip on the top of the breaker box. I got the same results.

Grounding rods have no part in the proper operation of the circuit under normal conditions. The "expert" gave you bum scoop.

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Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.

Also, how can the 220 work without the neutral to complete the circuit?

Thanks.

A 220 (240) volt circuit doesn't use a neutral. It is starting to sound like the wiring to the pump house isn't done correctly. From your description of the underground wires, black with white stripe, is appears that you have USE feeding your pump house. Maybe that white striped wire isn't connected to the neutral bar at the meter. Without pictures we won't get far with this.

Thanks everyone. I will have the electric company check the neutral wire for a break.

FYI, I buried a new wire this morning from another breaker box in my barn (that breaker box is on a separate feed) to my well house. I used the new 120v breaker in the breaker box in the barn and all is working flawlessly.